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  • Java - How to declare table[i][j] elements as instance variables?

    - by JDelage
    All, I am trying to code a Connect4 game. For this, I have created a P4Game class and a P4Board class which represents the i X j dimensions of the Connect4 board. In P4Game, I have the following: public class P4Game{ //INSTANCE VARIABLES private int nbLines; private int nbColumns; private P4Board [][] position; //CONSTRUCTOR public P4Game(int nbLines, int nbColumns){ this.nbColumns = nbColumns; this.nbLines = nbLines; P4Board [][] position = new P4Board [nbLines][nbColumns]; //Creates the table to receive the instances of the P4Board object.*/ for (int i=0; i<nbLines; i++){ for (int j=0; j<nbColumns; j++){ this.position[i][j] = new P4Board(i,j); //Meant to create each object at (line=i, column=j) } } } This causes a NullPointerException in the nested loops where I mention this.position[i][j]. I reference those objects in other methods of this class so I need them to be instance variables. I suppose the exception is due to the fact that I have not listed the table element position[i][j] as an instance variable at the beginning of the class. my question to people here is (1) is my assumption correct, and if so (2) what would be the syntax to declare instance variables of this form? Thank you all for your help with what I realize is a very basic question. Hopefully it will also benefit other newbies. Cheers, JDelage

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  • EXC_BAD_ACCESS with NSUserdefaults on iphone.

    - by Andreas Johannessen
    I have the following code in my ApplicationDelegate. My deployment target is 3.0 and upwards, however I get a EXC_BAD_ACCESS when I launch the app with the following code on my iPhone with 3.1.3, however on the simulator which has 4.2 it runs fine. I would really appriciate help on this one, thanks in advance. When I comment this block when I deploy to 3.1.3 device it runs without bad access. + (void)initialize { NSString *path = [[NSBundle mainBundle] bundlePath]; NSString *pListPath = [path stringByAppendingPathComponent:@"Settings.bundle/Root.plist"]; NSDictionary *pList = [NSDictionary dictionaryWithContentsOfFile:pListPath]; NSMutableArray *prefsArray = [pList objectForKey:@"PreferenceSpecifiers"]; NSMutableDictionary *regDictionary = [NSMutableDictionary dictionary]; for (NSDictionary *dict in prefsArray) { NSString *key = [dict objectForKey:@"Key"]; if(key) { id value = [dict objectForKey:@"DefaultValue"]; [regDictionary setObject:value forKey:key]; } } [[NSUserDefaults standardUserDefaults] registerDefaults:regDictionary]; } UPDATE: I traced the error to happen on this line: [[NSUserDefaults standardUserDefaults] registerDefaults:regDictionary]; So there is probaly another syntax on earlier iOS, or am I wrong?

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  • WPF ProgressBar - TargetParameterCountException

    - by Dr_Asik
    I am making my first WPF application, where I use the Youtube .NET API to upload a video to Youtube using the ResumableUploader. This ResumableUploader works asynchronously and provides an event AsyncOperationProgress to periodically report its progress percentage. I want a ProgressBar that will display this progress percentage. Here is some of the code I have for that: void BtnUpload_Click(object sender, RoutedEventArgs e) { // generate video uploader = new ResumableUploader(); uploader.AsyncOperationCompleted += OnDone; uploader.AsyncOperationProgress += OnProgress; uploader.InsertAsync(authenticator, newVideo.YouTubeEntry, new UserState()); } void OnProgress(object sender, AsyncOperationProgressEventArgs e) { Dispatcher.BeginInvoke((SendOrPostCallback)delegate { PgbUpload.Value = e.ProgressPercentage; }, DispatcherPriority.Background, null); } Where PgbUpload is my progress bar and the other identifiers are not important for the purpose of this question. When I run this, OnProgress will be hit a few times, and then I will get a TargetParameterCountException. I have tried several different syntax for invoking the method asynchronously, none of which worked. I am sure the problem is the delegate because if I comment it out, the code works fine (but the ProgressBar isn't updated of course). Thanks for any help.

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  • How to link a table to a field a in MySQL server

    - by Nek
    I have this data from a xml file: <?xml version="1.0" encoding="utf-8" ?> <words> <id>...</id> <word>...</word> <meaning>...</meaning> <translation> <ES>...</ES> <PT>...</PT> </translation> </words> This forms the table named "words", which has four fields ("id","word","meaning" and "translation"). On the other hand, the "translation" field can hold several languages like ES,PT,EN,JA,KO,etc... So I create a table ("words.translation", one field is "id" and the others ones are languages ids like "ES","PT",...). I'm sorry for this newby question, but I'd like to know a couple of things about this one-to-many relationship. How to join (or link?) this two tables in MySQL? What information does the "translation" field in the "words" table has to store? How is the sql query to get all the word information (JOIN syntax used?) Thanks for your patience.

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  • jQuery selector for option tag value attribute returns null

    - by Ben
    Hello, I am trying to change the selected option in a select dropdown box with jQuery. I have it set so that it finds the hash tag at the end of the URL and based on that hash tag it changes the selected option in the select box. Most of my code is functional, it successfully finds the hash tag and executes the if statement that corresponds with it. However, when it goes to execute the "then" section of the statement when it goes to the selector for the option (which uses an attribute selector based on the value attribute of the option tag) it returns null. If figured this out with firebug, in the console it says that the selector is null. Here is my code: $(document).ready(function() { var $hash = window.location.hash if($hash == "#htmlcss") { $('option[value="HTML/CSS Coding"]').attr("selected","selected") } if($hash == "#php") { $('option[value="PHP Coding"]').attr("selected","selected") } if($hash == "#jscript") { $('option[value="Javascript and jQuery Coding"]').attr("selected","selected") } if($hash == "#improv") { $('option[value="General Website Improvements"]').attr("selected","selected") } if($hash == "#towp") { $('option[value="Website Conversion to Wordpress"]').attr("selected","selected") } if($hash == "#wptheme") { $('option[value="Wordpress Theme Design"]').attr("selected","selected") } if($hash == "#complete") { $('option[value="Complete Website Creation"]').attr("selected","selected") } if($hash == "#server") { $('option[value="Web Server Configuration"]').attr("selected","selected") } }); So to clarify, when I enter in a url that ends in the #php hash tag, for example, the desired action does not occur which would change the "PHP Coding" option to the selected one by using the "selected" html attribute however the selector for the particular option tag returns null. Is there a problem with my syntax or is my code not functioning in the way that I think it should? Thanks very much.

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  • Learning C++ as a Perl programmer

    - by meneldor
    Hello all, I'm a Perl5 programmer for 7 years and I'm trying to learn C++ now. Some of the c++ syntax is hard for me to understand and to think in c++ way. For example: In perl you can mix the data in the arrays @array = (1,"string",5.355); You can assign any value to a scalar variable: $var = 1; $var = "string"; $var = \$reference_to_scalar; There are many examples. The friend of mine recommend me the book "Thinking of C++" by Bruce Eckel, but I haven't any C background and it's hard for me to understand some things. So my question is - could you recommend me a book for this situation. I don't want to learn C. I understand OOP (I'm getting more familiar with C++ oop aswell), I understand the point of the pointers(and some arithmetic) and references(widely used in perl). I dont need some of the manuals for dummies (what is int,bool,double,if,while), I just need a direction how to learn C++ from my point of perl programmer, because I,m sure that there are many like me. Thank you in advance.

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  • [PHP] Weird problem with dynamic method invocation

    - by Rolf
    Hi everyone, this time, I'm facing a really weird problem. I've the following code: $xml = simplexml_load_file($this->interception_file); foreach($xml->children() as $class) { $path = str_replace('__CLASS_DIR__',CLASS_DIR,$class['path']); if(!is_file($path)) { throw new Exception('Bad configuration: file '.$path.' not found'); } $className = pathinfo($path,PATHINFO_FILENAME); foreach($class as $method) { $method_name = $method['name']; $obj = new $className(); var_dump(in_array($method_name,get_class_methods($className)));exit; echo $obj->$method_name();### not a method ??? } } As you can see, I get the class name and method name from an XML file. I can create an instance of the class without any problem. The var_dump at the end returns true, that means $method_name (which has 2 optional parameters) is a method of $className. BUT, and I am pretty sure the syntax is correct, when I try: $obj-$method_name() I get: Fatal error: Method name must be a string If you have any ideas, pleaaaaase tell me :) Thanks in advance, Rolf

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  • NHibernate query against the key field of a dictionary (map)

    - by Carl Raymond
    I have an object model where a Calendar object has an IDictionary<MembershipUser, Perms> called UserPermissions, where MembershipUser is an object, and Perms is a simple enumeration. This is in the mapping file for Calendar as <map name="UserPermissions" table="CalendarUserPermissions" lazy="true" cascade="all"> <key column="CalendarID"/> <index-many-to-many class="MembershipUser" column="UserGUID" /> <element column="Permissions" type="CalendarPermission" not-null="true" /> </map> Now I want to execute a query to find all calendars for which a given user has some permission defined. The permission is irrelevant; I just want a list of the calendars where a given user is present as a key in the UserPermissions dictionary. I have the username property, not a MembershipUser object. How do I build that using QBC (or HQL)? Here's what I've tried: ISession session = SessionManager.CurrentSession; ICriteria calCrit = session.CreateCriteria<Calendar>(); ICriteria userCrit = calCrit.CreateCriteria("UserPermissions.indices"); userCrit.Add(Expression.Eq("Username", username)); return calCrit.List<Calendar>(); This constructed invalid SQL -- the WHERE clause contained WHERE membership1_.Username = @p0 as expected, but the FROM clause didn't include the MemberhipUsers table. Also, I really had to struggle to learn about the .indices notation. I found it by digging through the NHibernate source code, and saw that there's also .elements and some other dotted notations. Where's a reference to the allowed syntax of an association path? I feel like what's above is very close, and just missing something simple.

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  • Can someone tell me what this Java class does? I/O related

    - by anon
    I am relatively new to Java and trying to learn the I/O syntax. Could someone give me a general overview of what this code does? Thanks!! import java.io.*; public class FileReader { private String openFile=""; private String saveFile=""; FileReader(openFile, saveFile) { this.openFile=openFile; this.saveFile=saveFile; } public String process(){ System.out.println(this.openFile); System.out.println(this.saveFile); BufferedReader open=null; FileReader openFR=null; FileWriter save=null; int counter=0; String output=""; if(openFile.equals("")){ return "No open file specifified\n"; } if(this.saveFile.equals("")){ return "No save file specified\n"; } try { openFR = new FileReader(this.openFile); open = new BufferedReader(openFR); } catch (FileNotFoundException e) { return ("Open file no longer exists\n"); } try { save = new FileWriter(saveFile); } catch (IOException e){ return ("Error saving the file\n"); } try{ String temp = open.readLine(); while(temp != null){ temp = open.readLine(); counter++; save.write(output + "\n"); } } catch (IOException e){ e.getStackTrace(); return ("Error reading open file"); } try { save.flush(); } catch (IOException e) { e.printStackTrace(); return ("Error writing save file"); } return "Operation completed successfully"; } }

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  • How do I use .htaccess to redirect to a URL containing HTTP_HOST?

    - by Jon Cram
    Problem I need to redirect some short convenience URLs to longer actual URLs. The site in question uses a set of subdomains to identify a set of development or live versions. I would like the URL to which certain requests are redirected to include the HTTP_HOST such that I don't have to create a custom .htaccess file for each host. Host-specific Example (snipped from .htaccess file) Redirect /terms http://support.dev01.example.com/articles/terms/ This example works fine for the development version running at dev01.example.com. If I use the same line in the main .htaccess file for the development version running under dev02.example.com I'd end up being redirected to the wrong place. Ideal rule (not sure of the correct syntax) Redirect /terms http://support.{HTTP_HOST}/articles/terms/ This rule does not work and merely serves as an example of what I'd like to achieve. I could then use the exact same rule under many different hosts and get the correct result. Answers? Can this be done with mod_alias or does it require the more complex mod_rewrite? How can this be achieved using mod_alias or mod_rewrite? I'd prefer a mod_alias solution if possible. Clarifications I'm not staying on the same server. I'd like: http://example.com/terms/ - http://support.example.com/articles/terms/ https://secure.example.com/terms/ - http://support.example.com/articles/terms/ http://dev.example.com/terms/ - http://support.dev.example.com/articles/terms/ https://secure.dev.example.com/terms/ - http://support.dev.example.com/articles/terms/ I'd like to be able to use the same rule in the .htaccess file on both example.com and dev.example.com. In this situation I'd need to be able to refer to the HTTP_HOST as a variable rather than specifying it literally in the URL to which requests are redirected. I'll investigate the HTTP_HOST parameter as suggested but was hoping for a working example.

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  • Initialize Static Array of Structs in C

    - by russell_h
    I implementing a card game in C. There are lots of types of cards and each has a bunch of information, including some actions that will need to be individually scripted associated with it. Given a struct like this (and I'm not certain I have the syntax right for the function pointer) struct CARD { int value; int cost; // This is a pointer to a function that carries out actions unique // to this card int (*do_actions) (struct GAME_STATE *state, int choice1, int choice2); }; I would like to initialize a static array of these, one for each card. I'm guessing this would look something like this int do_card0(struct GAME_STATE *state, int choice1, int choice2) { // Operate on state here } int do_card1(struct GAME_STATE *state, int choice1, int choice2) { // Operate on state here } extern static struct cardDefinitions[] = { {0, 1, do_card0}, {1, 3, do_card1} }; Will this work, and am I going about this the right way at all? I'm trying to avoid huge numbers of switch statements. Do I need to define the 'do_cardN' functions ahead of time, or is there some way to define them inline in the initialization of the struct (something like a lambda function in python)? I'll need read-only access to cardDefinitions from a different file - is 'extern static' correct for that? I know this is a lot of questions rolled into one but I'm really a bit vague about how to go about this. Thanks.

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  • Rails select box in form decides on create action in controller?

    - by dannymcc
    Hi Everyone? I am trying to add a select box to the base of my create form that decides if an action runs from the controller...if that makes any sense? Basically the application creates a project in FreeagentCentral whenever a new project is made: def create @company = Company.find(params[:kase][:company_id]) @kase = @company.kases.create!(params[:kase]) respond_to do |format| params[:send_to_freeagent] ? @kase.create_freeagent_project(current_user) #flash[:notice] = 'Case was successfully created.' flash[:notice] = fading_flash_message("Case was successfully created.", 5) format.html { redirect_to(@kase) } format.xml { render :xml => @kase, :status => :created, :location => @kase } end end and within my form I have: <%= check_box_tag :send_to_freeagent, 1 % Create project in Freeagent? What I would like to happen, is if the select box is checked the project is sent to Freeagent. If not, the case just gets created locally as normal but without the Freeagent data being sent. If I use the above code, I get an exception caught error: SyntaxError in KasesController#new controllers/kases_controller.rb:114: syntax error, unexpected '\n' Any idea what I am doing wrong, also is it possible to make the check boxes checked as default? Thanks, Danny

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  • c++ File input/output

    - by Myx
    Hi: I am trying to read from a file using fgets and sscanf. In my file, I have characters on each line of the while which I wish to put into a vector. So far, I have the following: FILE *fp; fp = fopen(filename, "r"); if(!fp) { fprintf(stderr, "Unable to open file %s\n", filename); return 0; } // Read file int line_count = 0; char buffer[1024]; while(fgets(buffer, 1023, fp)) { // Increment line counter line_count++; char *bufferp = buffer; ... while(*bufferp != '\n') { char *tmp; if(sscanf(bufferp, "%c", tmp) != 1) { fprintf(stderr, "Syntax error reading axiom on " "line %d in file %s\n", line_count, filename); return 0; } axiom.push_back(tmp); printf("put %s in axiom vector\n", axiom[axiom.size()-1]); // increment buffer pointer bufferp++; } } my axiom vector is defined as vector<char *> axiom;. When I run my program, I get a seg fault. It happens when I do the sscanf. Any suggestions on what I'm doing wrong?

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  • Manifesto for Integrated Development Environments

    - by Hugo S Ferreira
    Have you recently take a peek at Coda, or Espresso, or Textmate? Or even Google Chrome's Developer Tools? They are well designed, intuitive, interface rich, and extensible. But Coda, Espresso or Textmate, among several, are text editors, not IDEs. On the other side, VIM and Emacs live in the last century, and Eclipse is an overbloated platform. This is more like an outcry for a decent, common infrastructure for REAL IDEs. But there's some questions attached: (i) what features are needed for such a product and (ii) what products are out there that could fullfil this need, and what are they missing. So here's my draft for a manifesto: Manifesto for Integrated Development Environments: We favor interactivity and productivity over syntax and tools. We favor inline, contextual documentation over man and html files. We favor high-definition, graphic-capable color screens over 80x25 character terminals. We favor the use of advanced input schemas over unintuitive keyboard shortcuts. We favor a common, extensible and customizable infrastructure over unmaintained chaintools. We know the difference between search&replace and refactoring. We know the difference between integrated debugging support over a terminal window. We know the difference between semantic-aware code-completion over dumb textual templates. We favor the usage of standards like (E)BNF.

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  • MySQL get point in time totals from related tables

    - by batfastad
    Hi everyone We have an order book and invoicing system and I've been tasked with trying to output monthly rolling totals from these tables. But I don't know really where to start with this. I think there's some SQL syntax that I don't even know about yet. I'm familiar with INNER/LEFT/JOINS and GROUP BY etc but grouping by date is confusing since I don't know how to limit the data to only the current date that's being grouped by at that point. I think this will involve joining the tables to themselves or possibly a sub-select. I always thought it best to avoid sub-selects apart from when absolutely necessary. Basically the system has 3 tables orders: order_id, currency, order_stamp orders_lines: order_line_id, invoice_id, order_id, price invoices: invoice_id, invoice_stamp order_stamp and invoice_stamp are UTC unix timestamps stored as integers, not MySQL timestamps. I'm trying to get a listing by year/month showing the total of current unbilled orders (sum of price), at that point in time. Current orders are ones where order_stamp is less than or equal to 00:00 on the 1st of the month. Unbilled orders are ones where invoice_stamp is null or invoice_stamp is greater than 00:00 on the 1st of the month. At that point in time there may not be a related invoice yet and invoice_id might be null. Anyone got any suggestions on what I should join to what and what I need to group by? Cheers, B

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  • Java: how do I get a class literal from a generic type?

    - by Tom
    Typically, I've seen people use the class literal like this: Class<Foo> cls = Foo.class; But what if the type is generic, e.g. List? This works fine, but has a warning since List should be parameterized: Class<List> cls = List.class So why not add a <?>? Well, this causes a type mismatch error: Class<List<?>> cls = List.class I figured something like this would work, but this is just a plain ol' a syntax error: Class<List<Foo>> cls = List<Foo>.class How can I get a Class<List<Foo>> statically, e.g. using the class literal? I could use @SuppressWarnings("unchecked") to get rid of the warnings caused by the non-parameterized use of List in the first example, Class<List> cls = List.class, but I'd rather not. Any suggestions? Thanks!

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  • How to encapsulate a third party complex object structure?

    - by tangens
    Motivation Currently I'm using the java parser japa to create an abstract syntax tree (AST) of a java file. With this AST I'm doing some code generation (e.g.: if there's an annotation on a method, create some other source files, ...) Problem When my code generation becomes more complex, I've to dive deeper into the structure of the AST (e.g. I have to use visitors to extract some type information of method parameters). But I'm not sure if I want to stay with japa or if I will change the parser library later. Because my code generator uses freemarker (which isn't good at automatic refactoring) I want the interface that it uses to access the AST information to be stable, even if I decide to change the java parser. Question What's the best way to encapsulate complex datastructures of third party libraries? I could create my own datatypes and copy the parts of the AST that I need into these. I could create lots of specialized access methods that work with the AST and create exactly the infos I need (e.g. the fully qualified return type of a method as one string, or the first template parameter of a class). I could create wrapper classes for the japa datastructures I currently need and embed the japa types inside, so that I can delegate requests to the japa types and transform the resulting japa types to my wrapper classes again. Which solution should I take? Are there other (better) solutions to this problem?

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  • Numerical calculations in Prolog

    - by user8472
    While reading SICP I came across logic programming chapter 4.4. Then I started looking into the Prolog programming language and tried to understand some simple assignments in Prolog. I found that Prolog seems to have troubles with numerical calculations. Here is the computation of a factorial in standard Prolog: f(0, 1). f(A, B) :- A > 0, C is A-1, f(C, D), B is A*D. The issues I find is that I need to introduce two auxiliary variables (C and D), a new syntax (is) and that the problem is non-reversible (i.e., f(5,X) works as expected, but f(X,120) does not). Naively, I expect that at the very least C is A-1, f(C, D) above may be replaced by f(A-1,D), but even that does not work. My question is: Why do I need to do this extra "stuff" in numerical calculations but not in other queries? I do understand (and SICP is quite clear about it) that in general information on "what to do" is insufficient to answer the question of "how to do it". So the declarative knowledge in (at least some) math problems is insufficient to actually solve these problems. But that begs the next question: How does this extra "stuff" in Prolog help me to restrict the formulation to just those problems where "what to do" is sufficient to answer "how to do it"?

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  • Is there an application that can help someone create an XML document based on the Relax NG schema?

    - by meowsqueak
    I've spent a bit of time creating a Relax NG schema for use within our team to validate XML documents we use for exchanging information. The schema is not complicated, but it is reasonably large. I am wondering if there exists a tool that can read in such a Relax NG schema and assist a user in creating a corresponding instance document, using the schema as a template. Perhaps an application with a GUI that creates fields and drop-down selections for each part of the document? For example, the tool might create an outline XML document and prompt the user to select multiples of certain elements, fill in each field, perhaps with permitted values read directly from the schema. It might also show the user via visual feedback when their document is 'complete', or highlight validation problems as they come up. I could anticipate writing a custom GUI tool to create such an XML document, but I'd really like changes to the schema to be automatically reflected by the GUI - and I really wonder if this hasn't already been done. I know some editors can automatically validate an XML document against a schema as it's being written, but I would really like to get my users one step away from the XML so they don't have to worry about the details of the XML syntax.

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  • What are the lengths/limits C preprocessor as a language creation tool? Where can I learn more about

    - by Weston C
    In his FAQ @ http://www2.research.att.com/~bs/bs_faq.html#bootstrapping, Bjarne Stroustrup says: To build [Cfront, the first C++ compiler], I first used C to write a "C with Classes"-to-C preprocessor. "C with Classes" was a C dialect that became the immediate ancestor to C++... I then wrote the first version of Cfront in "C with Classes". When I read this, it piqued my interest in the C preprocessor. I'd seen its macro capabilities as suitable for simplifying common expressions but hadn't thought about its ability to significantly add to syntax and semantics on the level that I imagine bringing classes to C took. So now I have a couple of questions on my mind: 1) Are there other examples of this approach to bootstrapping a language off of C? 2) Is the source to Stroustrup's original work available anywhere? 3) Where could I learn more about the specifics of utilizing this technique? 4) What are the lengths/limits of that approach? Could one, say, create a set of preprocessor macros that let someone write in something significantly Lisp/Scheme like?

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  • how to store a file handle in perl class

    - by Haiyuan Zhang
    please look at the following code first. #! /usr/bin/perl package foo; sub new { my $pkg = shift; my $self = {}; my $self->{_fd} = undef; bless $self, $pkg; return $self; } sub Setfd { my $self = shift; my $fd = shift; $self_->{_fd} = $fd; } sub write { my $self = shift; print $self->{_fd} "hello word"; } my $foo = new foo; My intention is to store a file handle within a class using hash. the file handle is undefined at first, but can be initilized afterwards by calling Setfd function. then write can be called to actually write string "hello word" to a file indicated by the file handle, supposed that the file handle is the result of a success "write" open. but, perl compiler just complains that there are syntax error in the "print" line. can anyone of you tells me what's wrong here? thanks in advance.

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  • Reversible numerical calculations in Prolog

    - by user8472
    While reading SICP I came across logic programming chapter 4.4. Then I started looking into the Prolog programming language and tried to understand some simple assignments in Prolog. I found that Prolog seems to have troubles with numerical calculations. Here is the computation of a factorial in standard Prolog: f(0, 1). f(A, B) :- A > 0, C is A-1, f(C, D), B is A*D. The issues I find is that I need to introduce two auxiliary variables (C and D), a new syntax (is) and that the problem is non-reversible (i.e., f(5,X) works as expected, but f(X,120) does not). Naively, I expect that at the very least C is A-1, f(C, D) above may be replaced by f(A-1,D), but even that does not work. My question is: Why do I need to do this extra "stuff" in numerical calculations but not in other queries? I do understand (and SICP is quite clear about it) that in general information on "what to do" is insufficient to answer the question of "how to do it". So the declarative knowledge in (at least some) math problems is insufficient to actually solve these problems. But that begs the next question: How does this extra "stuff" in Prolog help me to restrict the formulation to just those problems where "what to do" is sufficient to answer "how to do it"?

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  • Adding defaults and indexes to a script/generate command in a Rails Template?

    - by charliepark
    I'm trying to set up a Rails Template that would allow for comprehensive set-up of a specific Rails app. Using Pratik Naik's overview (http://m.onkey.org/2008/12/4/rails-templates), I was able to set up a couple of scaffolds and models, with a line that looks something like this ... generate("scaffold", "post", "title:string", "body:string") I'm now trying to add in Delayed Jobs, which normally has a migration file that looks like this: create_table :delayed_jobs, :force => true do |table| table.integer :priority, :default => 0 # Allows some jobs to jump to the front of the queue table.integer :attempts, :default => 0 # Provides for retries, but still fail eventually. table.text :handler # YAML-encoded string of the object that will do work table.text :last_error # reason for last failure (See Note below) table.datetime :run_at # When to run. Could be Time.now for immediately, or sometime in the future. table.datetime :locked_at # Set when a client is working on this object table.datetime :failed_at # Set when all retries have failed (actually, by default, the record is deleted instead) table.string :locked_by # Who is working on this object (if locked) table.timestamps end So, what I'm trying to do with the Rails template, is to add in that :default = 0 into the master template file. I know that the rest of the template's command should look like this: generate("migration", "createDelayedJobs", "priority:integer", "attempts:integer", "handler:text", "last_error:text", "run_at:datetime", "locked_at:datetime", "failed_at:datetime", "locked_by:string") Where would I put (or, rather, what is the syntax to add) the :default values in that? And if I wanted to add an index, what's the best way to do that?

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  • Formatting associative array declaration

    - by Drew Stephens
    When declaring an associative array, how do you handle the indentation of the elements of the array? I've seen a number of different styles (PHP syntax, since that's what I've been in lately). This is a pretty picky and trivial thing, so move along if you're interested in more serious pursuits. 1) Indent elements one more level: $array = array( 'Foo' => 'Bar', 'Baz' => 'Qux' ); 2) Indent elements two levels: $array = array( 'Foo' => 'Bar', 'Baz' => 'Qux' ); 3) Indent elements beyond the array constructor, with closing brace aligned with the start of the constructor: $array = array( 'Foo' => 'Bar', 'Baz' => 'Qux' ); 4) Indent elements beyond the array construct, with closing brace aligned with opening brace: $array = array( 'Foo' => 'Bar', 'Baz' => 'Qux' ); Personally, I like #3—the broad indentation makes it clear that we're at a break point in the code (constructing the array), and having the closing brace floating a bit to the left of all of the array's data makes it clear that this declaration is done.

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  • XPath ordered priority attribute search

    - by user94000
    I want to write an XPath that can return some link elements on an HTML DOM. The syntax is wrong, but here is the gist of what I want: //web:link[@text='Login' THEN_TRY @href='login.php' THEN_TRY @index=0] THEN_TRY is a made-up operator, because I can't find what operator(s) to use. If many links exist on the page for the given set of [attribute=name] pairs, the link which matches the most left-most attribute(s) should be returned instead of any others. For example, consider a case where the above example XPath finds 3 links that match any of the given attributes: link A: text='Sign In', href='Login.php', index=0 link B: text='Login', href='Signin.php', index=15 link C: text='Login', href='Login.php', index=22 Link C ranks as the best match because it matches the First and Second attributes. Link B ranks second because it only matches the First attribute. Link A ranks last because it does not match the First attribute; it only matches the Second and Third attributes. The XPath should return the best match, Link C. If more than one link were tied for "best match", the XPath should return the first best link that it found on the page.

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